Bug#852543: Apache doesn't start anymore with sysvinit

[ROUSSEAU Dominique <d.rousseau@nnx.com>]

Package: apache2
Version: 2.4.25-2
Followup-For: Bug #852543

Dear Maintainer,

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I have a fresh install of Stretch where I explicitly installed sysvinit-core after system install.
So the "systemd" package *is* installed but init is handled SysV-way.

The modification introduced between 2.4.25-1 and 2.4.25-2 falsely believe that systemd is used for services by checking two things :
- that /var/run/systemd exists (it does on this server)
- that /bin/systemctl is executable (it does on this server)

Some extra check probably need to be put for checking whether pid 1 IS actually systemd


-- Package-specific info:

-- System Information:
Debian Release: 9.0
  APT prefers testing
  APT policy: (500, 'testing')
Architecture: amd64 (x86_64)

Kernel: Linux 4.8.0-2-amd64 (SMP w/2 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: sysvinit (via /sbin/init)

Versions of packages apache2 depends on:
ii  apache2-bin          2.4.25-2
ii  apache2-data         2.4.25-2
ii  apache2-utils        2.4.25-2
ii  dpkg                 1.18.18
ii  init-system-helpers  1.46
ii  lsb-base             9.20161125
ii  mime-support         3.60
ii  perl                 5.24.1~rc4-1
pn  perl:any             <none>
ii  procps               2:3.3.12-3

Versions of packages apache2 recommends:
ii  ssl-cert  1.0.38

Versions of packages apache2 suggests:
pn  apache2-doc                                      <none>
pn  apache2-suexec-pristine | apache2-suexec-custom  <none>
pn  www-browser                                      <none>

Versions of packages apache2-bin depends on:
ii  libapr1                  1.5.2-5
ii  libaprutil1              1.5.4-3
ii  libaprutil1-dbd-sqlite3  1.5.4-3
ii  libaprutil1-ldap         1.5.4-3
ii  libc6                    2.24-8
ii  libldap-2.4-2            2.4.44+dfsg-3
ii  liblua5.2-0              5.2.4-1.1+b1
ii  libnghttp2-14            1.17.0-1
ii  libpcre3                 2:8.39-2
ii  libssl1.0.2              1.0.2j-5
ii  libxml2                  2.9.4+dfsg1-2.1
pn  perl:any                 <none>
ii  zlib1g                   1:1.2.8.dfsg-4

Versions of packages apache2-bin suggests:
pn  apache2-doc                                      <none>
pn  apache2-suexec-pristine | apache2-suexec-custom  <none>
pn  www-browser                                      <none>

Versions of packages apache2 is related to:
ii  apache2      2.4.25-2
ii  apache2-bin  2.4.25-2

-- no debconf information